#pragma once
#include<iostream>
#include<assert.h>
using namespace std;

namespace wuge
{
	class string
	{
	public:

		typedef char* iterator;
		typedef const char* const_iterator;
		iterator begin()
		{
			return _str;
		}
		iterator end()
		{
			return _str + _size;
		}

		const_iterator begin() const
		{
			return _str;
		}
		const_iterator end() const
		{
			return _str + _size;
		}

		string(const char* str = "")
		{
			_size = strlen(str);
			_capacity = _size;
			_str = new char[_capacity + 1];
			strcpy(_str, str);
		}

		~string()
		{
			if (_str)
			{
				delete[] _str;
				_str = nullptr;
				_size = _capacity = 0;
			}
		}

		const char* c_str() const
		{
			return _str;
		}

		size_t size() const
		{
			return _size;
		}

		size_t capacity() const
		{
			return _capacity;
		}

		char& operator[](size_t pos)
		{
			assert(pos < _size);

			return _str[pos];
		}

		const char& operator[](size_t pos) const
		{
			assert(pos < _size);

			return _str[pos];
		}

		void reserve(size_t n);
		void push_back(char ch);
		void append(const char* str);
		string& operator+=(char ch);
		string& operator+=(const char* str);

	private:
		char* _str = nullptr;
		size_t _size = 0;
		size_t _capacity = 0;
	};
	void test_string1();
	void test_string2();

}